[Garan]

You can change the size of the "floating" labels that appear in game. In the Options control panel (press Ctrl+O to open), go to the UI settings tab and there is a slider control for "Floating Text Size".

You can also resize many of the individual UI display panels which will also increase/decrease the font for those panels. At the bottom of the UI Settings tab of the Options control panel, there are sliders for the panels that can be resized. You may have to play with them a bit since the scaling method used can cause bluring at many of the scaling values.

I'm not aware of any way to change the font face, but there are a lot of options in the UserPreferences.ini file that can not be modified in-game through the UI, so it's possible that there could be an undocumented setting that can be modified there to change the font face.